The international patent application No. PCT/IT2012/000209 of the same applicant discloses a multiple-lane fruit positioning apparatus, especially suitable for peaches, comprising a frame and a fruit flight conveyor advancing in the longitudinal direction of said frame, the fruit holding flights being shaped with a number of recesses spaced apart transversely, each recess being provided at the bottom with an opening through which a part of the fruit protrudes. Placed under the fruit holding flights is a device for the orientation of the fruits including a multiplicity of transverse shafts, spaced apart longitudinally, each of them bearing a number of orienting elements spaced apart transversely as said number of recesses. Each orienting element, which is rotatable integrally with each transverse shaft bearing it, finds itself in said opening of recess in contact with the fruit contained therein and moves the fruit in order to position orthogonally to the longitudinal direction the plane containing the suture line of each fruit and its stalk cavity facing downwards.
A drawback linked to an automatic operation of orientation such as that obtained in the apparatus of the above cited patent application, is that the automatic operation of orientation does not ensure that the suture plane of each fruit is positioned parallel to the vertical cutting plane that is orthogonal to the fruit advancing lane. This is due to the fact that the stalk cavity in the fruits is not always so evident that it is combined perfectly with the orienting element. This is, ultimately, a blind positioning of the fruits. It follows that not all the fruits reach, at the cutting station, the above mentioned positioning with a result that the cut is not perfect.
The present invention is based on the detection of the suture line of each fruit so as to achieve its individual orientation.
U.S. Pat. No. 6,691,854 describes a device for orienting fruits. The device has a holder conveyor with holders for the fruits, lifts synchronously co-displaceable with the holders and rotatable relative thereto for lifting the fruits out of the holders and rotating the fruits into, a detector, such as a camera, for detecting the position of each fruit and a control device for the lifts which is connected to the detector and which activates the lifts for a relevant object as long as is required to rotate each single fruit.
EP 2167408 provides a system for the automatic determination of the position and orientation of a fruit placed on rollers, said fruit comprising at least one rotation axis. This European patent starts from the fact that a fruit has a steady and predictable movement on the rollers as a result of a rotation of one or both of the rollers. For example, an apple will rotate around its axis crown-stem or about an axis perpendicular to this. The knowledge of the predictable rotation movements of said fruit allows for the automatic determination of the orientation and position of the fruit within a short time interval using a vision system suitable for the acquisition and analysis of images of the rotating fruit. This information on orientation and position of the fruit can subsequently be used for manipulating the fruit, for instance by a robot suitable for packaging fruit in a desired position and orientation.
Both the above mentioned US patent and European patent aim to an ordered packing of fruits, especially apples, and use, associated with a vision system, a hourglass- or diabolo-shaped roller conveyor that allows an automatic orientation on a statistical basis of each fruit.
It should be evident that these inventions serve mainly to place a fruit in such a way that its central axis is vertical, but they would not be useful to orient a fruit, whose axis is already vertical, so that the cross-section plane containing the suture line is positioned parallel to the cutting plane of the fruit.
Further the inventions described in the cited patents would not give any indication on the precise definition of a line such as the suture line of a peach.